Surface domain potential difference-mediated efficient charge separation on a defective ZnIn2S4 microsphere photocatalyst

Low-efficiency charge separation in metal sulfides is a major obstacle to realizing high photocatalytic performance. Herein, we propose the concept of a similar surface domain potential difference between adjacent microdomains with and without surface S vacancies on ZnIn₂S₄ to mediate charge separation. Defective ZnIn₂S₄ microspheres (DZISNPs) are prepared through a solvothermal method combined with a low-temperature hydrogenation surface engineering strategy. The as-prepared DZISNPs with a narrowed bandgap of 2.38 eV possess a large specific surface area of 178.5 m² g^?1, a pore size of 6.89 nm, and a pore volume of 0.36 cm³ g^?1, which further improves the visible light absorption. The resultant DZISNPs exhibit excellent visible light activity (2.15 mmol h^?1 g^?1), which is ～two-fold higher than that of the original DZISNP. The experimental results and DFT calculations reveal that the enhanced property can be a result of the surface S vacancy-induced surface domain potential difference, promoting the spatial separation of electrons and holes. Furthermore, the long-term stability of the DZISNPs indicates that the formation of surface S vacancies can inhibit the photocorrosion of ZnIn₂S₄. This strategy provides new insights for fabricating highly efficient and stable sulfide photocatalysts.     

N-Alkylation of amines with alcohols catalyzed by a Cp*Ir complex

A new effective catalytic system consisting of [Cp*IrCl₂]₂/K₂CO₃ (Cp*=pentamethylcyclopentadienyl) for the N-alkylation of primary amines with alcohols has been developed. As an example, the reaction of aniline with benzyl alcohol in the presence of [Cp*IrCl₂]₂ (5.0 mol%Ir) and K₂CO₃ (5.0 mol%) in toluene at 110°C for 17 h gave benzylaniline in an isolated yield of 88%.     

Hydrothermal solidification of diatomaceous earth with analcime formation

Diatomaceous earth (DE) solidifies hydrothermally with analcime formation. With analcime formation, strength development was much greater than that with calcium silicate hydrate (CSH) formation. NaOH addition conditioned analcime formation because NaOH solution not only promoted dissolution of quartz and montmorillonite but also provided Na⁺ to form the analcime. Curing temperature and time affected analcime formation, and, in this study, over 6 h (at 200 °C) and 175 °C (for 12 h), analcime seemed to form readily. After hydrothermal treatment, the skeletons of diatoms can still be seen in the solid after analcime formation but can hardly be found after CSH formation.     

One-step synthesis of mesoporous two-line ferrihydrite for effective elimination of arsenic contaminants from natural water

Mesoporous two-line (2-lines) ferrihydrite is successfully synthesized by a facile one-step method. The ferrihydrite is characterized by X-ray diffraction (XRD), Raman spectrum, N(2) adsorption, scanning electron microscopy (SEM), and transmission electron microscopy (TEM). The 2-lines ferrihydrite with mesoporous structure possesses excellent adsorption performance for arsenic (As(III)) contamination. Experimental results show that As(III) contamination can be effectively removed within 2 h by this 2-lines ferrihydrite, which is attributed to the special mesoporous structure and large surface area (133 m(2) g(-1)). The As(III) loading capacity of our obtained mesoporous 2-lines ferrihydrite is up to 128 mg(As) g(-1)(Fe). In addition, As(III) can be easily desorbed from 2-lines ferrihydrite by simple heat treatment in alkali solution. After reusage for 10 times, it still presents good adsorption performance, indicating the excellent stability of the 2-lines ferrihydrite. Furthermore, the mesoporous 2-lines ferrihydrite is also effective for As(III) removal when some natural water constituents are present. Therefore, the high adsorption capability of the mesoporous 2-lines ferrihydrite makes it a potentially attractive adsorbent for the removal of As(III) contamination from natural water.     

Hydrothermal synthesis of pollucite with soil and incineration ash for Cs immobilization and its immobilizing mechanism and leaching property

Journal of Radioanalytical and Nuclear Chemistry - A hydrothermal method has been developed to convert Cs-polluted soil (kaolin) mixed with incineration ashes of plants (rice husk ash) into...     

惯性组合导航系统的一种分布式实时调度算法

惯性组合导航系统是多处理机多任务的舰用分布式实时系统。本文在此环境下改进了一种分布式实时操作系统的调度算法，给出了改进前后调度算法的结果比较。本文还设计并研制了此调度模型的性能分析系统ＰＤＡＡ（ＰｒｅｄｉｃｔｉｖｅＤｅａｄｌｉｎｅＡｌｇｏｒｉｔｈｍＡｎａｌｙｓｉｓ），并给出了一个应用实例。     

Hydrothermal solidification of municipal solid waste incineration fly ash

Hydrothermal solidification of municipal solid waste incineration (MSWI) fly ash has been conducted under saturated steam pressure at 200 °C for up to 48 h with quartz addition. To enhance the strength of solidified specimens further, the raw fly ash was pre-treated by water-washing and mixed with NaOH solution (2 M) as reaction solvent. Experimental results showed that curing time and temperature had significant effects on strength development. Strength development was found to be mainly due to tobermorite formation, and addition of quartz and NaOH solution promoted tobermorite formation. The raw fly ash could also be used as an additive to solidify MSWI bottom ash, and with raw fly ash addition (10%) the flexural strength of solidified specimens reached more than 21 MPa, suggesting high potential to recycle 100% MSWI ash (e.g. as 10% fly ash + 90% bottom ash). Leaching tests were conducted to determine amounts of heavy metals dissolved from solidified specimens. The results showed that under the hydrothermal conditions of this study, leaching of heavy metals was very low. As such, the hydrothermal processing method might have high potential for recycling/reusing MSWI fly ash on a large scale.